Focal Plane Detector Package for PREX-II
Abstract
The Pb Radius Experiment, PREX, aims to make a high precision, statistics limited measurement of a sub-ppm parity violating asymmetry. To achieve this goal in relatively short time requires high (GHz-level) scattered flux rates on the main integrating detectors. As a result, the PREX-II main detectors employ radiation-hard, high-purity Spectrosil 2000 fused-silica tiles as an active Cerenkov medium for counting electrons. Each tile is optically polished and coupled to a photo-multiplier tube with a quartz window for UV light transmission. The focal plane detector packages also each include three 10x20 cm2 active area GEM tracking planes for Q2 normalization, and two auxiliary quartz detectors for monitoring parity non-violating asymmetry backgrounds from any residual transverse polarization of the electron beam. Detailed studies of expected flux rates, detector photo-electron yields, and pmt gains have been made in order to optimize the detector design as well as test and minimize the systematic uncertainty associated with pmt non-linearity. In this talk, we will present the design of the PREX-II focal plane detector package and report on the key performance parameters achieved during the experiment.
NSF Award No.'s 1307340 and 1615146.- Publication:
-
APS Division of Nuclear Physics Meeting Abstracts
- Pub Date:
- 2019
- Bibcode:
- 2019APS..DNP.RD003M